Observation of Complete Orbital Two-Channel Kondo Effect in van der Waals Ferromagnet Fe3GaTe2.

The orbital two-channel Kondo (2CK) effect is one of the crucial systems with non-Fermi liquid (NFL) behavior. But the full three-regime transport evidence has never been observed in one sample. Here, all three resistive regimes for the orbital 2CK effect induced by two-level systems (TLSs) have been observed in the van der Waals ferromagnet Fe3GaTe2. Electron behavior undergoes a continuous transition from electron scattering to NFL behavior, and subsequently to Fermi liquid behavior. The magnetic field does not affect any regimes, indicating the nonmagnetic origin of the TLSs in Fe3GaTe2. In addition, instead of topological Hall, the slope of a linear negative magnetoresistance is related to spin-magnon scattering and could be utilized to infer the emergence of spin textures. Our findings indicate that Fe3GaTe2 may be an ideal platform to study electron correlation and topological phenomena.